On 2023/10/10 16:19, Tian, Kevin wrote:
From: Liu, Yi L <yi.l.liu@xxxxxxxxx> Sent: Monday, October 9, 2023 4:51 PM +struct iommufd_device *iommufd_device_bind_pasid(struct iommufd_ctx *ictx, + struct device *dev, + u32 pasid, u32 *id) +{ + struct iommufd_device *idev; + int rc; + + /* + * iommufd always sets IOMMU_CACHE because we offer no way for userspace + * to restore cache coherency. + */ + if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY)) + return ERR_PTR(-EINVAL); + + /* + * No iommu supports pasid-granular msi message today. Here we + * just check whether the parent device can do safe interrupts. + * Isolation between virtual devices within the parent device + * relies on the parent driver to enforce. + */ + if (!iommufd_selftest_is_mock_dev(dev) && + !msi_device_has_isolated_msi(dev)) { + rc = iommufd_allow_unsafe_interrupts(dev); + if (rc) + return ERR_PTR(rc); + } +Only MemWr w/o pasid can be interpreted as an interrupt message then we need msi isolation to protect.
yes.
But for SIOV all MemWr's are tagged with a pasid hence can never trigger an interrupt. From this angle looks this check is unnecessary.
But the interrupts out from a SIOV virtual device do not have pasid (at least today). Seems still need a check here if we consider this bind for a SIOV virtual device just like binding a physical device. -- Regards, Yi Liu
